This invention relates to a technique for utilizing information derived from a large number of sensor nodes connected to a network. More specifically, this invention relates to a technique for managing information transmitted by sensor nodes capable of moving among nodes.
Recently, techniques of sensor network systems for acquiring sensing data obtained from a large number of sensor nodes via networks are being developed. In the sensor network systems, information acquired by the large number of sensor nodes is utilized via networks by computers and apparatuses installed at places apart from the sensor nodes.
In the sensor network systems, sensing data acquired by the large number of sensor nodes is transmitted via repeating stations and base stations to a server computer and the like, and the server computer collects information of the respective sensor nodes. In the sensor network systems with the structure as described above, when the sensing data acquired by the sensor nodes is directly transmitted to host server computers, traffic amounts of the sensor network systems become huge, and it becomes difficult for the host server computers to specify necessary information. Thus, there are known sensor network systems in which only sensing data satisfying preset process conditions among pieces of sensing data acquired by sensor nodes is transmitted to host server computers (refer to, for instance, JP-A-11-39034).